The Kittila mine is located in the Lapland region of northern Finland, approximately 900 km north of Helsinki and 150 km north of the Arctic Circle. The climate is moderated by the Gulf Stream off the coast of Norway, such that northern Finland’s climate is comparable to that of eastern Canada and mining work can be carried out year-round. Kittila’s proven and probable mineral reserves contain 3.7 million ounces of gold (27.3 million tonnes grading 4.20 g/t gold) as at December 31, 2022, and mine life is estimated through 2035.
The Kittila property covers 205 square km, stretching 25 km along the Suurikuusikko Trend, a major gold-bearing shear zone. The mine area includes a group of six gold deposits along a 4.5-km segment of the trend. The largest of the deposits is the Main Zone in the Suuri, Roura and Rimpi areas that contain most of the current mineral reserves and mineral resources at Kittila. The other deposits are the undeveloped Sisar Zone, which is sub-parallel to the Main Zone, as well the Etela and Ketola zones.
As part of a major expansion project at Kittila, the commissioning of the expanded mill with its 25% increase in capacity was completed ahead of schedule in 2020.
The sinking of a 1,044-metre deep shaft as part of the expansion project was completed in 2022. Initial rock hoisting from the shaft started in the first quarter of 2023, with the ramping up of the hoist capacity continuing in the second quarter. The shaft project is expected to be completed in the third quarter of 2023.
The expansion project is expected to increase the efficiency of the mine and decrease or maintain current operating costs while providing access to the deeper mining horizons. This increased mining rate will be supported by the development of the Sisar Zone and deeper portions of the Main Zone.
Geology
The region around the Kittila mine is underlain by mafic volcanic and sedimentary rocks of the Kittila Greenstone Belt that trend north to north-northeast and are nearly vertical. This greenstone belt is similar to those hosting our Canadian deposits in the Abitibi region and Nunavut. The contact between iron-rich and magnesium-rich volcanic and sedimentary rocks consists of a transitional zone (the “Porkonen Formation”) varying between 50 and 200 metres in thickness. This zone is strongly sheared, brecciated and characterized by intense hydrothermal alteration and gold mineralization, features consistent with major brittle ductile deformation zones. The zone is part of a major north-northeast-oriented shear zone (the “Suurikuusikko Trend”). The Porkonen Formation hosts the Kittila gold deposit, which contains multiple mineralized zones stretching over a strike length of more than 25 km.
Mineralization
Work has focused on a 4.5-km segment of the Suurikuusikko Trend that hosts the six main zones of known gold mineral reserves and mineral resources – Ketola, Etela, Suuri, Roura, Rimpi and Sisar. The Sisar Zone is located to the east of the main Kittila ore zone, and in proximity to existing underground infrastructure. Gold mineralization in these zones is associated with intense hydrothermal alteration (carbonate-albite-sulphide), and is almost exclusively refractory, locked inside the fine-grained sulphide minerals arsenopyrite and pyrite. The remainder is free gold, which is manifested as extremely small grains of gold in pyrite.
Mining
The underground mining method is open stoping followed by delayed backfill. Approximately 16 km of tunnels are developed each year to ensure sufficient ore production is available to keep the mill supplied. After extraction, stopes are filled with cemented backfill or paste backfill to allow the safe mining of adjacent stopes. Ore is trucked to the surface crusher using underground haul trucks via the 4,400-metre-long ramp access system. Once fully commissioned, the new 1,044-metre-deep shaft will have hoisting capacity of 2.7 million tonnes per year (2.0 million tonnes of ore and 0.7 million tonnes of waste). In addition, the shaft is expected to provide access to the mineral resource areas below 1,150 metres depth, where ongoing exploration programs show promising results.
Processing
At Kittila’s processing plant, ore is treated by grinding, flotation, pressure oxidation, and carbon-in-leach circuits. Kittila has Agnico Eagle’s only pressure oxidation circuit (autoclave), which is required because of the ore’s refractory nature. Gold from the leach circuit is recovered from the carbon in a Zadra elution circuit and recovered from solution using electrowinning, and then smelted in an electric induction furnace and poured into doré bars. Gold recovery of 86% is expected over the life of the mine. Ore is processed in a surface processing plant with a current capacity of 6,000 tonnes per day.
The mill expansion was completed ahead of schedule and on budget in 2020 at a cost of €29.5 million. The work involved installation of a secondary crushing circuit, new thickener and reactor capacity, and minor modifications to the existing grinding circuit and autoclave.
In 2020, the Company was granted the permits to expand mine production to 2.0 Mta and the use of a new discharge location. The new discharge waterline construction was completed and commissioned at the end of 2020.
A nitrogen removal plant was commissioned in the first quarter of 2023 and is performing well. Total nitrogen reduction is close to 80% and ahead of expectations.
The Company continues to rely on the current mining permit of 1.6 Mtpa while maintaining operational flexibility to reach an expanded 2.0 Mtpa volume in the event of a positive decision by the Supreme Administrative Court of Finland restore the permits granted by Regional State Administrative Agency of Northern Finland in 2020 to expand operations to 2.0 Mtpa.
Exploration
Exploration at the Kittila mine is focused on extending the Main and Sisar zones northward, southward and at depth in the Suuri, Roura and Rimpi areas to increase the mineral reserves in the large orebody. Sisar is subparallel to and 50 to 300 metres east of the main Kittila mineralization and remains open at depth and along strike.
At the Kittila mine in 2023, the Company expects to spend approximately $10.6 million for 68,500 metres of drilling, focused on the Main Zone in the Roura and Rimpi areas as well as the Sisar Zone. The drilling includes 53,000 metres of capitalized conversion drilling at the mine as described above and 15,500 metres of expensed exploration drilling. The expensed drilling will be focused on targets beyond the current mineral reserve area, especially from 1,500 to 2,000 metres depth and at shallower depths in the area north of the mine.